Process of granulating nitrate of lime and similar substances without dephlegmation and dust.



PROCESS OF GRANULATING 1,203,740. No Drawing? ALFRED noL'rEn, OF RJUKAN, NORWAY,

KVELSTOFAKTIESELSKAB, OE GHBJSTIANIA, NORWAY.

I Toall whom it may concern:

make and use the same.

Be it known that I, ALFRED HoLTnR, a subject of the King of Norway, resldin'g at Rjukan, Norway, have invented certain new and useful Improvements in Processes of Granulating Nitrate of Lime and Similar Substances without Dephlegmation and Dust; and I do herebydeclare the follow ing to be a full, clear, and exact description of-the invention, such as will enable others skilled in the art to-whi'ch it appertainsto This invention has for'its object a process of-reducing nitrate of lime and other salts to a finely divided state without the formation of dust.

In the production of many materials in a coarsely pulverized state it is a great inconvenience that the same will contain much of the material in the form of powder so that the material on being further treated Wlll make much. dust. This is a very great in convenience especially in fertilizers spread by hand, the consequence being that said fertilizers cannot be spread in windy -weather .as' they are carried, by the wind anywhere elsebut where they ought to be;

- moreover the laborers will be highly soiled,

marked if the substance is at the same time hygroscopic. It has been proposed to treat the dust will penetrate into the respiratory or ans and ma thuscause diseases etc.

These inconveniences -;will be particularly the commercial, dusty fertilizers in various ways to avoid the formationjof dust, by

adding oils, etc. No one however has hither- 1 .to succeeded in removing thedust in a satisfactory manner exceptat excessive cost:

I have now found that salts or fertilizers of the said kind, which will melt without being decomposed and which may either. be

anhydrous or hydrous, may be granulated in a very simple manner, if'the following what manner nitrate of lime "Norgessalpeter may be treated so as to produce a granular material perfectly free from dust and which is eminently adapted'for spreading by hand. 7

The molten nitrate o'f limeconcentrated to crystalline .consistency is caused to flow on to a perforated bottom or'plate disposed across. a shaft orthe like so that, on the Specification ofLetters Patent.

NITRATE or LIME SIMILAR SUBSTANCES WITHOUT DEPHLEeMa'rIoiv AND DUST;

. molten massflowing out through the perforations there-will be formed sufliciently small ASSIGNOR ro NORSK HYDno-ELEk'rRIsK Patented Nov. *7; 1916.

Application filed anuar'y 6, 1914. Serial No. 810,661. I l

drops of the'ma'terial. Saiddrops will fall into the shaft. If now the size of the drops and the temperature be controlled in accordance with the length" of the shaft, the drops 'will be solidified before reaching the bottom of the shaft. Thisbottom is so constructed that the grains will be removed the moment they reach the bottom, Y

Itis not necessary. that the saltpeter should be solidified into a mass ofstony hardness before'reaching the bottom of the shaft; it is suflicientthat the solidification has come to such a point that the' grains will not be sticky and form lumps. The further hardening will then take place during the transport to the storage bins.

To reducethe dimensions of the shaft, air,- which may. be cooled, maybe forced through velocity of. the air the smaller the dimensions ,to which the shaft has to be made. In the case-of a hygroscopic substance itis of advantage to make the air, that is conducted through the shaft, circulate through a .;'coo1- ing apparatus, to avoid the. introduction of;

moisture in the materiaL-tbe moisture originally contained in the air being quickl gab-f sorbed by the material first passed-throughthe air.-

Likewise, to obtain a speedy tion of the drops,'some of the same substance may be added 'in-a' pulverized solid statefto the liquid mass immediately before the drops are formed, which, as is wellj-known, will,-

assist solidification. I I

Since. there are several substances which in a liquid condition will not stand exposure to the air, inert gases, suchasf for instance carbonic apid,may be used instead, of 7 air. for circulation in theshaft. 'By reason of the circulation-of the gases in the apparatus, the loss ,will be exceedingly slightso that but slight quantities of freshgases will be required for covering said loss.

The molten substance under treatment may also bereduced into a state of drops in other ways than "the. one" above described. Thus nozzles of various kinds may be used for, this purpose such as tangential nozzles,

in which a rotary motion is imparted to'the liquid its passage through thenozzle, or injector-shaped nozzles may be used and the fine division of the molten substance 4 be produced by means of air under pressure the solidification of the substance is brought about, by free motion through air or other gas.

I claim,

1. The process of granulating nitrate of lime and similar fertilizing substances without theformation of powder, which consists in forming a melt-of the substance, and when the substance is in'condition for crystallization producing granules or drops thereof of crystalline consistency, and efiecting the hardening of such'drops by causing them to move freely through an inert gaseous atmosphere.

2-. The process of granulating nitrate of lime and. the like without the formation of powder, which consists in forming a melt thereof, and when sufliciently concentrated for crystallization producing granules or drops of said molten salt, and causing such drops to move freely in a counter current with a suitable inert gas.

'3. The process of granulating nitrate of lime and the like without the formation of powder, which consists in forming a melt thereof, and when sufiiciently concentrated for crystallization producing granules or drops of said molten salt and causing 'such drops to move freely in counter current with air. 0

4. Theprocess of granulating nitrate of lime and the likewith'out the formation of powder, which consists in forming a melt thereof, and when in condition for crystallization producing granules or drops of said molten salt, and causing such drops to move freely in counter current with a suitable inert gas, said gas being maintained in circulation.

5. Theprocess of granulating nitrate of lime and the like without the formation of powder, which consists in forming a melt thereof, and when in condition for crystallization producing granules or drops'ofsaid molten salt, and causing such drops to move freely in counter current with a suitable inert gas, said gas being maintained in circulation While being cooled.

6. The process of granulating nitrate of lime and similar substance, which consists in producing a melt thereof and adding to this melt a solid pulverized salt, forming the melt into drops and immediately thereafter causing the drops or granules so produced to move freely in a counter current with a suitable inert gas.

7. The process of granulating fertilizers capable of dieing melted, which comprises forming a melt of the substance, causing themelt to be in condition for crystallization, producing drops or ranules of the melt and causing said drops to move freely through a current of a dry cooling gas counter to the movement of the drops, said current of gas being of suflicient force to retard the fall of said granules.

8. The process of granulating fertilizers capable ofbeing readily melted, which comprises forming a melt of the substance, producing drops or granules of the melt, causing said drops to freely fall through a counter'current of a dry inert gas, and circulating the gas through the pathof the falling drops, and cooling the gas at a point of its circuit outside of the path of the drops.

9. The process of granulating'nitrate of lime, which comprises forming a melt thereof, mixing therewith finely divided nitrate trate of lime, said fertilizer being in small globules for ready distribution by hand.

' In testimony that l claim the foregoing as myinvention, ll-have signed my name in presence of two subscribing witnesses.

ALFRED HOLTER.

Witnesses: i

. M. GUT'rnNnr IN, R TH Linnsraom.

of lime to initiate crystallization, imme- 

